I think lightning network is the next closet. You are correct in that you still need internet, but CBDCs will as well. For lightning you will either need to ho

I think lightning network is the next closet. You are correct in that you still need internet, but CBDCs will as well. For lightning you will either need to host your own node, or rely on a third party node. Lightning offers a high degree of privacy and fungibility, no exchanges needed, and freezing is not possible. ~2 second confirmation, final settlement. It is backed by the Bitcoin network which is extremely secure, and not very generous with attack surfaces. To doublespend on it an attacker would need to use more hashpower (energy) than what the network is currently being secured by. As it would require an enormous amount of resources, and since it is nearly impossible to pull off, mostly now attacks are trying to convince the general population to not use it with fear based tactics, general misinformation, and half truths; which should give you a good idea of how valuable it really is over any permissioned digital money. Good luck!